Source: Supplied.

Red Bull KTM’s Marvin Musquin has broken through for his first-career Monster Energy AMA Supercross 450SX main event victory in a drama-filled night at Arlington, Texas.

Musquin withstood pressure from runner-up Cole Seely (Team Honda HRC) in the 20-minute plus one-lap final, after holeshotting the restarted race and never being headed on his way to the win.

Taking his first podium of the season was Jason Anderson (Rockstar Energy Husqvarna) in third, while red plate-holder Ryan Dungey (Red Bull KTM) worked his way from outside the top 10 to fourth, making his way by Anderson’s teammate Dean Wilson in the final stages.

Chaos broke out toward the midway point, as firstly Cooper Webb (Monster Energy/Yamalube/Chaparral/Yamaha Financial Services/Yamaha) dropped out of second with a flat tyre, returning for P14. He earlier led the red-flagged first portion of the final.

Almost directly after Webb’s issues, Eli Tomac (Monster Energy) crashed out of a podium at speed and damaged his front brake in the process. He pitted and rectified the issue, only to circulate for a 15th-place finish at race’s end.

Australia’s Chad Reed (Monster Energy/Yamalube/Chaparral/Yamaha Financial Services/Yamaha) was also forced to pit during the final late in what became a race of attrition, credited two laps down in 19th overall.

All that now means that Dungey has an 18-point lead in the standings over teammate Musquin, with Seely also moving by Tomac for position into third. The latter’s now 29 points outside of the lead.

A pivotal West Coast 250SX main event – in the series’ final outing before the series heads east – saw Justin Hill and Austin Forkner deliver a 1-2 finish for Monster Energy/Pro Circuit/Kawasaki.

Early series points leader Shane McElrath (Troy Lee Designs/Red Bull/KTM) looked to be on course for a third win of the season, although under pressure from Hill, until mechanical dramas put him out of contention in a disastrous turn of events.

It was lap 16 of the eventual 20 completed when trouble struck McElrath, exiting the track and then ultimately dropping all the way down the order to 22nd as a result. He’s now third in the standings, 25 points behind Hill.

Behind Hill and Forker came a charging Aaron Plessinger (Yamalube/Star Racing/Yamaha), climbing to second in the points but 21 outside of the lead, while Jimmy Decotis (GEICO Honda) and Dan Reardon (Yamalube/Star Racing/Yamaha) filled the top five.

Reardon’s result was another season-best in a consistent showing, now seventh in the championship standings entering the break. Countryman Hayden Mellross (51FIFTY Energy Drink Yamaha) returned for a solid ninth-place finish, matching his career-high.

The 2017 championship will now travel to Minneapolis, Minnesota, next Saturday, 18 February, for round seven of 450SX and the East Coast 250SX season-opener.